How to make a for loop variable const with the exception of the increment statement?

Question

Consider a standard for loop:

for (int i = 0; i < 10; ++i) 
{
   // do something with i
}

I want to prevent the variable i fr

Answer 1

template
void while_less(T n, F f, T start = 0){
    for(; start < n; ++start)
        f(start);
}

int main()
{
    int s = 0;
    
    while_less(10, [&](auto i){
        s += i;
    });
    
    assert(s == 45);
}

maybe call it for_i

No overhead https://godbolt.org/z/e7asGj